JPH1028879A - Ion exchange resin improved in washability and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ion exchange resin good in regeneration rate and excellent in washability by introducing an ion exchange group into a cross-linked copolymer obtained by copolymerizing a monovinyl monomer and a specific cross-linkable monomer in a specific ratio. SOLUTION: An ion exchange resin high in the diffusion speed of inorg. ions and excellent in regeneration ratio is obtained by copolymerizing 20-99.9mol.% of a monovinyl monomer and 0.1-80mol.% of a cross-linked monomer represented by the general formula (wherein n is an integer of 1-5) to obtain a cross-linked copolymer and introducing an ion exchange group thereinto. At this time, the moisture content of the ion exchange resin is set to 50wt.%. As the cross-linking monomer, bis(vinylphenyl)ethane is used and, as the monovinyl monomer, styrene is used and, as the ion exchange group, a sulfo group is used. As the ion exchange group, pref., a quanternary ammonium base-N<+> R1 R2 R3 X-(wherein R1 to R3 are a 1-4C alkyl and X is an anion) is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an ion exchange resin having improved water washability, suitable for producing ultrapure water, and a method for producing the same.

[0002]

2. Description of the Related Art Generally, an ion exchange resin comprises a monovinyl monomer and a polyvinyl monomer as a crosslinking monomer.
Spherical cross-linked copolymers are obtained by suspension polymerization in water and then synthesized by introducing ion-exchange groups in an appropriate manner (Takayuki Otsu and Masayoshi Kinoshita, published by Kagaku Dojin, “Polymer Synthesis” Experimental Method "(1972), 373-3
See page 75).

When synthesizing this crosslinked copolymer, styrene is often used as a monovinyl monomer. Also,
As the crosslinking monomer, a polyvinyl compound having two or more polymerizable vinyl groups is effective, and examples thereof include divinylbenzene, divinylxylene, trivinylbenzene, ethylene glycol dimethacrylate, trimethylolpropanetrimethacrylate, divinylpyridine, and divinylnaphthalene. Can be Of these, divinylbenzene is often used as a crosslinking monomer in the production of ion exchange resins due to its chemical stability. However, it has been pointed out that styrene and divinylbenzene have heterogeneous copolymer structures due to the difference in their reactivity (D
avankov V. A. Rogoshin S., et al.
V. , Tsyurupa M .; P. Angew. ma
cromol. Chem. , 32 (1), 145, 1
973), it has been pointed out that the non-uniformity may hinder substance diffusion inside.

Have disclosed bis (p-vinylphenyl) hexane, bis (p-
When using vinyl phenyl) decane and having a relatively high moisture content in the resin having a crosslinking monomer content of 4% by weight or less, the diffusion of organic ions having a high molecular weight such as triethylbenzylammonium ion and methylene blue causes divinylbenzene as a crosslinking monomer. (Hurnal Prik)
ladoi Khimii, 46 (12), 2779-
2782 (1973)).

However, there is no mention of what happens in the case of a crosslinked polymer having a low water content or diffusion of a low molecular weight substance. On the other hand, in the case of an ion-exchange resin comprising a styrene / divinylbenzene copolymer, it is also known that the amount of a regenerant required for regeneration increases in an ion-exchange resin having a high divinylbenzene content and a low water content and a high degree of crosslinking. (See Diaion Manual I, published by Mitsubishi Chemical Corporation, 1990, 3rd edition, page 58), suggesting the existence of a structure that suppresses the diffusion of inorganic ions.

[0006]

SUMMARY OF THE INVENTION The present inventors provide an ion exchange resin having a high inorganic ion diffusion rate and an excellent regeneration rate, and a method for producing the same.

[0007]

As a result of investigations to solve these problems, the production of a copolymer using a specific cross-linking monomer enables the production of a copolymer from a conventional styrene / divinylbenzene copolymer. It has been found that it is possible to produce an ion-exchange resin having a higher regeneration rate and an improved water-washing property than the synthesized ion-exchange resin. That is, 1 of the present invention comprises 20 to 99.9 mol% of a monovinyl monomer,
Crosslinkable monomer represented by the following general formula (1): 0.1 to 8
0 mol%

[0008]

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An ion-exchange resin in which an ion-exchange group is introduced into a crosslinked copolymer obtained by copolymerizing (wherein n is an integer from 1 to 5). In addition, 2 of the present invention
Is a method for producing an ion-exchange resin in which a monovinyl monomer and a cross-linking monomer are copolymerized in the presence of a polymerization initiator and an ion-exchange group is introduced into the obtained cross-linked copolymer, wherein at least the following general formula (1)

[0010]

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A method for producing an ion-exchange resin, comprising using a bis (vinylphenyl) alkane represented by the following formula (where n represents an integer from 1 to 5). The details of the present invention will be described below.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The ion-exchange resin of the present invention can be produced by using bis (vinylphenyl) alkane as a crosslinking monomer and using a technique generally used for producing an ion-exchange resin. (1) Monovinyl monomer Examples of the monovinyl monomer include styrene compounds such as styrene, vinylnaphthalene, vinyltoluene, ethylvinylbenzene, vinylchlorobenzene and chloromethylstyrene, and aromatic monovinyl monomers such as vinylpyridine. preferable. These are 20 to 99.5 mol%, preferably 50 to 90 mol%, of the monomer.
95 mol% is used. (2) Crosslinking monomer Bis (vinylphenyl) alkane used as a crosslinking monomer has the general formula (1)

[0013]

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(Wherein, n represents an integer of 1 to 5)
Wherein the alkylene group is bonded at the m-position or the p-position with respect to the vinyl group, and the combination is any of (m, m), (m, p), and (p, p). Each pure product or a mixture thereof. Specific examples of bis (vinylphenyl) alkane include bis (vinylphenyl) methane, bis (vinylphenyl) ethane,
Bis (vinylphenyl) propane, bis (vinylphenyl) butane, and bis (vinylphenyl) pentane.
As the bis (vinylphenyl) alkane, bis (vinylphenyl) ethane, which is relatively easy to synthesize and can be industrially manufactured at low cost, is particularly preferable. When a bis (vinylphenyl) alkane having a long alkylene group with n of 6 or more is used, cyclization is performed by an intramolecular crosslinking reaction,
It is not preferable because it may not efficiently act as a crosslinking monomer.

These bis (vinylphenyl) alkanes can be synthesized by a known technique. Specifically, a method of coupling vinylphenylalkyl chloride having various alkyl groups by a Wurtz reaction in the presence of magnesium and iodine, and a method described in Polymer Journal (“Polymer Journal”, No. 1)
3, No. 7, page 635), and can be produced by various methods such as a method by a dehydration reaction of an α-phenylethyl alcohol compound. Further, bis (vinylphenyl) alkane may be used as a mixture with another crosslinking monomer having at least two or more vinyl groups, for example, divinylbenzene, ethylene glycol dimethacrylate, and the like described above.

The crosslinking monomer is bis (vinylphenyl)
The total amount of the alkane and the vinyl monomer having at least two or more vinyl groups is 0.1% to the total amount of the monomer.
It is preferably about 80 mol%. In order to control the water content of the ion-exchange resin, that is, the proportion of water in the water-swelled ion-exchange resin to 50% or less, the total amount of the crosslinking monomer is more preferably 5 to 50 mol%. When a mixture of vinyl monomers having at least two or more vinyl groups is used, bis (vinylphenyl) alkane is preferably used in an amount of 5 to 50 mol% based on the whole monomers.

Examples of the crosslinking monomer having at least two vinyl groups include divinylbenzene, trivinylbenzene, divinyltoluene, divinylnaphthalene, divinylxylene, ethylene glycol dimethacrylate,
Examples include diethylene glycol dimethacrylate and trimethylolpropane trimethacrylate. Of these, divinylbenzene is preferred.

(3) Other copolymer components In addition to the above-mentioned monovinyl monomer, bis (vinylphenyl) alkane, and other cross-linking monomers, if necessary, addition-polymerizable monomers may be used as copolymer components. It is possible. Specific examples of the addition polymerizable monomer include methyl methacrylate, ethyl methacrylate, alkyl methacrylate such as propyl methacrylate, methyl acrylate, ethyl acrylate, alkyl acrylate such as propyl acrylate, methacrylic acid, acrylic Examples include acid, acrylonitrile, methacrylonitrile, butadiene, isoprene and the like.

(4) Polymerization initiator A known radical polymerization initiator can be used as a polymerization initiator for producing the three-dimensionally crosslinked skeleton copolymer in the present invention. Examples of the polymerization initiator include organic peroxides and azo compounds. The compound is effective. Specifically, azobisisobutyronitrile as an azo compound, azobisvaleronitrile, ketone peroxide as an organic peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxyester, Peroxydicarbonate, acetylacetone peroxide,
1,1-bis (t-butylperoxy) -3,3,5-
Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -2-methylcyclohexane, 1,1-
Bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroper Oxide, t-butyl cumyl peroxide, di-t
-Butyl peroxide, isobutyl peroxide,
Lauroyl peroxide, benzoyl peroxide, succinic peroxide, octanoyl peroxide, stearoyl peroxide, di-isopropylperoxydicarbonate, bis- (4-t-butylcyclohexyl) peroxydicarbonate, cumylperoxyneodeca Noate, t-butyl peroxyacetate, t-butyl peroxy neodecanoate, t-
Butyl peroxyisobutyrate, t-butyl peroxy laurate and the like are effective.

In the present invention, the amount of the polymerization initiator used is preferably 0.03% by weight or more and 5% by weight or less based on the raw material monomers. More preferably, the content is 0.1 to 2% by weight. (5) Polymerization method The polymerization temperature depends on the decomposition temperature of the polymerization initiator used, but is generally 30 to 95 ° C, preferably 50 to 90 ° C.
° C. In the present invention, the polymerization method is not particularly limited, but in order to form a spherical copolymer, the polymerization reaction is carried out in water or another aqueous medium while stirring the monomer mixture and the polymerization initiator at a relatively high speed. As the suspension stabilizer, a substance capable of maintaining and dispersing the monomer mixture more uniformly is used. Specifically, it is generally used in the production of ion exchange resins, and more specifically,
Preferred are polyvinyl alcohol, gelatin, xanthan gum, sodium, dodecyl sulfonate, sodium methacrylate, magnesium silicate, sodium cellulose glycolate, hydroxyethyl cellulose, methyl cellulose and the like. Usually, it is preferable to use the suspending agent at 0.05 to 1.0% by weight based on the water of the suspending medium. When a spherical copolymer is produced in the present invention, the volume ratio of the monomer mixture to the suspension medium is generally from 1:10 to 1:10.
Preferably, 1: 2, more suspension medium.

(6) Shape of Copolymer The copolymer produced in the present invention may be a porous body having pores or a gel body having no pore structure in its final form. In order to produce a porous copolymer, a method generally used for producing an ion exchange resin is used. Specifically, there is a method of performing a polymerization reaction by adding a porogen to the monomer mixture. As the porosifying agent, a water-insoluble organic solvent which dissolves the monomer well and does not swell the produced copolymer at all or substantially may be used. More specifically, organic solvents such as toluene, tert-amyl alcohol, sec-butanol, heptane, isooctane, tetrachloroethane, and dichlorobenzene are preferred.

Further, a mixture of a swelling agent having an affinity for a copolymer to be formed and a precipitant having no affinity for a monomer is dissolved in an organic solvent which is insoluble in water. After adding and polymerizing, a method of producing a porous copolymer by removing the additive solvent can also be used. Specifically, there is an example in which toluene and hexane are mixed and used. Further, a method of producing a porous copolymer by adding a linear polymer and a diluent thereof to a monomer mixture to carry out a polymerization reaction, and then removing the resulting mixture can be used. Specifically, there is an example in which a mixture of polystyrene and toluene is added.

(7) Ion Exchange Resin The shape of the ion exchange resin produced by the present invention may be other than spherical. Specifically, it may be in the form of a plate, a film, or a fiber. As a method for producing an ion exchange resin, there is a method described in JP-B-36-2192. According to this method, in the polymerization of a monovinyl monomer and a polyvinyl monomer, polymerization is performed while a monomer is newly added to the formed crosslinked copolymer during the polymerization reaction. Such a method can be used as a method for synthesizing a copolymer using the crosslinking monomer of the present invention. The thus obtained copolymer is converted into an ion exchange resin by adding a functional group by a conventional method,
use.

Specifically, a strongly acidic cation exchange resin containing a sulfonic acid (—SO ₃ H) or sulfonate (—SO ₃ M, M is usually an alkali metal ion) group; a carboxylic acid (—COOH) Or a carboxylate (—CO ₂ M,
M is a weakly acidic cation exchange resin having usually an alkali metal group; a quaternary ammonium group (—N ⁺ R ₁ R ₂ R ₃ X, R
_{1 to} R ₃ represent an alkyl group or an alkanol group;
Represents an anion); a strongly basic anion exchange resin; and a trialkylamino group (-NR ₁ R ₂ , R ₁ or R ₂ is usually an alkyl group or a hydroxyalkyl group)
Functional groups constituting a weakly basic anion exchange resin containing, specifically, sulfonamide, trialkylamino, tetraalkylammonium, carboxyl, carboxylate, sulfonic, sulfonate, hydroxyalkylammonium, phosphonate And other functional groups known in the field of ion exchange resins.

The functionalization reaction to convert the copolymer to an ion exchange resin includes sulfonation with concentrated sulfuric acid, amination following chlorosulfonation with chlorosulfonic acid, amination following reaction with sulfuryl chloride or thionyl chloride, and It is typified by amination following chloromethylation. When performing sulfonation with concentrated sulfuric acid, the sulfonation reaction rate can be controlled by the reaction temperature, reaction time, and amount of sulfuric acid.

When a conventional styrene / divinylbenzene copolymer is sulfonated into an ion-exchange resin, the reaction rate is increased and one sulfonic acid group is introduced per benzene ring molecule even if these reaction conditions are severe. That was difficult. However, when a copolymer prepared by using bis (vinylphenyl) alkane as a cross-linking monomer in the present invention is used, sulfones having a higher reaction rate under milder conditions, specifically, a lower temperature, a shorter reaction time, a smaller amount of sulfuric acid, and the like. Can be implemented.

Further, following the sulfonation reaction, an operation of removing waste sulfuric acid, specifically, an operation of gradually lowering the sulfuric acid concentration to remove the sulfuric acid from the reaction system is required. When the copolymer of the present invention is used, The amount of sulfuric acid used for the reaction is small,
As a result, there is an economic effect that the amount of waste sulfuric acid can be smaller than before. Similarly, in a functionalization reaction other than sulfonation, the reaction temperature, reaction time, and amount of reagent used in the reaction are more moderately lower than when a conventional styrene / divinylbenzene copolymer is used. With this, functionalization with a high conversion can be performed.

The water value of the ion exchange resin thus obtained is 70% by weight or less. This is the water value of a general ion exchange resin. The ion exchange resin obtained in the present invention is superior in performance to the ion exchange resin prepared from the conventional styrene / divinylbenzene copolymer when the moisture value is low. Specifically, it exhibits excellent performance in terms of the diffusion rate of a low molecular substance such as an inorganic ion, the regeneration rate, and the washing property. The superiority in performance is especially 50% by weight of water
Notable below.

The ion exchange resin thus obtained can be used in fields where ion exchange resins are conventionally used. Specifically, it can be used for deionization or ion exchange from water or an aqueous solution. Specific applications are
Hard water softening, pure water production, metal recovery and separation, chemical solution purification, sugar solution purification, amino acid separation and purification, etc. Also, solid acidic catalysts,
As a solid basic catalyst, it can be used as a catalyst for organic reactions.
Specifically, Diaion Manual II (published by Mitsubishi Chemical Corporation, 1990, 3rd edition, pages 193 to 19)
(See page 9), it can be used as a catalyst for a hydrolysis reaction or the like.

The ion exchange resin of the present invention has an excellent regeneration rate, and can provide an economical effect in that the amount of the regenerating agent required for regeneration is small. In addition, the effect on environmental conservation can be expected in that the amount of waste generated in the regeneration process can be reduced. Further, it has a property of being excellent in water-washing properties, and in the water-washing step after passing various solutions, the concentration of residual substances can be reduced with a small amount of water.

A specific example of the use of the ion exchange resin obtained in the present invention is production of ultrapure water. In the production process of ultrapure water, which includes the step of removing ionic substances with an ion exchange resin, contamination due to leaching from the ion exchange resin has a significant effect on purity. It is common to remove pure substances by passing pure water through in advance, but this involves consuming part of the ultrapure water that is to be obtained in the manufacturing process, thereby reducing process efficiency. I have. The ion exchange resin of the present invention,
Since it is excellent in water washability, it is possible to remove eluted substances before use only by consuming a small amount of ultrapure water, and it is possible to operate the process efficiently.

As a more specific method of use, raw water is subjected to removal of suspended matter by coagulation filtration, followed by removal of ionic substances by ion-exchange resin to obtain deionized water, and furthermore, decomposition of organic substances by irradiation with ultraviolet rays, pressure reduction. Pure water is obtained through steps such as removal of dissolved gas below and removal of dissolved ions in a mixed bed of a strongly acidic cation exchange resin and a strongly basic anion exchange resin. The pure water is further decomposed into carbonic acid or carboxylic acid by irradiation with ultraviolet light of a short wavelength, treated with a strongly basic anion exchange resin, and mixed with a strongly acidic cation exchange resin and a strongly basic anion exchange resin in a mixed bed. The treatment removes ionic substances to obtain ultrapure water, but the ion exchange resin obtained in the present invention can be used in the step of treating pure water. The following examples illustrate the invention in detail,
The present invention is not limited by this embodiment. Unless otherwise specified,% is parts by weight.

[0033]

【Example】

[Production Example 1] <Synthesis of bis (1,4-vinylphenyl) ethane> 26.8 g of magnesium is added to 2 L of tetrahydrofuran, and 318 g of 4-chloromethylstyrene is gradually added with stirring. After completion of the reaction, the reaction residue was filtered and concentrated, and recrystallization with methanol was repeated to obtain bis (1,4-
(Vinylphenyl) ethane was obtained. [Production Example 2] <Synthesis of bis (1,4-vinylphenyl) butane> 13.4 g of magnesium is added to 1 L of tetrahydrofuran, and 138.6 g of 4-chlorostyrene is gradually added with stirring. Further, 1,4-dibromobutane was added and reacted to obtain bis (1,4-vinylphenyl) butane.

[Example 1] <Production of ion exchange resin> Bis (1,4-vinylphenyl) ethane 1 obtained in Production Example 1 was added to 528.8 g of styrene (molar ratio: 90.16 mol%).
29.9 g were mixed (9.84 mol% in molar ratio), and a polymerization initiator (general name: 1,1-bis (t-butylperoxy)) was added.
1.76 g of 2-methylcyclohexane, (Nippon Yushi Co., Ltd., “Perhexa MC” purity: 85%) was added, and in a 1976 ml aqueous solution in which polyvinyl alcohol was dissolved in deionized water to a concentration of 0.5%. The mixture was heated to 85 ° C. under stirring and polymerized to obtain a spherical crosslinked copolymer in a yield of 102%. 98% sulfuric acid 1 was added to 280 g of the obtained spherical copolymer.
400 g was added and heated to introduce sulfonic acid groups.
Thereafter, the residual sulfuric acid was gradually diluted and filtered, and then 2N-N
150 ml of aOH was added, and the obtained ion exchange resin was converted to Na type. The ion exchange capacity of the obtained ion exchange resin was 2.22 meq / ml. Water attached to the ion exchange resin sufficiently immersed in deionized water was centrifuged, and the ratio of the loss on drying to the weight before drying when vacuum-dried at 80 ° C. for 8 hours was measured as moisture. The water content is 38.
3%.

<Measurement of Regeneration Rate of Ion Exchange Resin> Resin 1
After filling the column with 5 ml and passing a 1N-HCl aqueous solution for 30 minutes so as to have a regeneration level of 100 g-HCl / LR, 1.5 BV of deionized water was passed at a constant rate, followed by regeneration. When the measured ion exchange capacity was measured,
91% of the total exchange capacity has been regenerated and the replay rate is 91%.
%Met. It was confirmed that the obtained ion exchange resin had an excellent regeneration rate. FIG. 1 shows the results. In addition, a dissolution test was performed. Fill the column with 80 ml of resin and add 1N
-HCl to 200 g-HCl / LR.
After passing through with 4, the mixture was washed with 2 BV of deionized water having a total organic carbon amount of 22.5 ppb with SV4. Thereafter, the same deionized water was passed through SV20, and the conductivity and the total amount of organic carbon were measured. FIG. 2 shows the results of conductivity measurement, and FIG. 3 shows the results of total organic carbon measurement. After the regeneration, it was confirmed that the conductivity and the total amount of organic carbon rapidly decreased.

Example 2 569.6 g of styrene and bis (1,4-vinylphenyl) ethane 8 obtained in Production Example 1
9.1 g (at a molar ratio of 6.50 mol%) were mixed to prepare an ion exchange resin in the same manner as in Example 1. The yield after polymerization was 96%. The obtained ion exchange resin had an ion exchange capacity of 1.94 meq / ml and a water content of 46.9%. When the regeneration rate of the obtained ion exchange resin was measured, the regeneration rate was 96.9% at a regeneration level of 100 g-HCl / LR, confirming that the resin had an excellent regeneration rate (FIG. 1).

Example 3 569.6 g of styrene and bis (1,4-vinylphenyl) ethane 4 obtained in Production Example 1
5.9 g (3.22 mol% in molar ratio) were mixed to prepare an ion exchange resin in the same manner as in Example 1. The yield after polymerization was 101%. The obtained ion exchange resin has an ion exchange capacity of 1.29 meq / ml and a water content of 62.2%.
Met. When the regeneration rate of the obtained ion exchange resin was measured, the regeneration rate was 100% at a regeneration level of 100 g-HCl / LR (FIG. 1).

[Comparative Example 1] The regeneration rate of "Diaion (registered trademark)" manufactured by Mitsubishi Chemical Corporation, which is an ion exchange resin using a styrene-divinylbenzene copolymer, was measured. A regeneration level of 100 g-HCl /
"Diaion SK104" and SK in LR
1B and the reproduction rate of the SK112 were measured. The results are shown in Table 1 and FIG.

[0039]

[Table 1]

Comparative Example 2 Divinylbenzene was used in place of bis (1,4-vinylphenyl) ethane. 518.8 g of styrene and 139.9 g of divinylbenzene (industrial grade, purity 56.5%) were mixed, and a polymerization reaction and a sulfonation reaction were carried out in the same manner as in Example 1 to obtain an ion exchange resin. The obtained ion exchange resin has an exchange capacity of 2.5
1 meq / ml and water content was 35.5%. Example 1
A dissolution test was performed in the same manner as described above. Compared with Example 1, it was found that both the conductivity and the total amount of organic carbon declined more slowly, and that more water was required for washing (FIGS. 2 and 3).

Example 4 The bis (1,4) obtained in Example 2
-Vinylphenyl) ethane and styrene copolymer 20g
120 g of chloromethyl methyl ether was added to
After stirring at 30 ° C. for 30 minutes to sufficiently swell the polymer, 10 g of zinc chloride was added as a catalyst and reacted at 50 ° C. for 8 hours to obtain a chloromethylated polymer. 10 g of the chloromethylated polymer is swollen with 10 ml of dioxane,
22 ml of 0% aqueous trimethylamine solution was added,
For 8 hours to obtain a tetraammonium type anion exchange resin (Cl type). Ion exchange capacity is 1.42m
eq / ml. When the water content was measured in the same manner as in Example 1, the water content was 45%.

Example 5 522.9 g of styrene and bis (1,4-vinylphenyl) ethane 3 obtained in Production Example 1
1.8 g (molar ratio: 2.5 mol%) and 36.5 g (purity: 2.5 mol%) of divinylbenzene having a purity of 56.5% were mixed, and 1.76 g of a polymerization initiator Perhexa MC was added. In a 1976 ml aqueous solution in which polyvinyl alcohol was dissolved to a concentration of 0.5%, the mixture was heated to 85 ° C. with stirring to obtain a spherical crosslinked copolymer. The yield after polymerization was 98%. Obtained spherical copolymer 200
1400 g of 98% sulfuric acid was added to the resulting mixture and heated to introduce sulfonic acid groups. Thereafter, the residual sulfuric acid was gradually diluted and filtered, and then 150 ml of 2N-NaOH was added to convert the obtained ion exchange resin to the Na type. The obtained ion exchange resin has an ion exchange capacity of 1.83 meq / m.
1, water content was 49.9%.

Example 6 Instead of bis (1,4-vinylphenyl) ethane, bis (1,4-vinylphenyl) obtained in Production Example 2 was used.
(Vinylphenyl) butane was used. 516.6 styrene
g and bis (vinylphenyl) butane (142.1 g, molar ratio: 10 mol%) were mixed, and a polymerization reaction and a sulfonation reaction were carried out in the same manner as in Example 1 to obtain an ion exchange resin. The obtained ion exchange resin has an exchange capacity of 2.58 meq /
ml, water content was 40.0%.

[0044]

According to the present invention, the amount of chemical substances used for regenerating the ion exchange resin is small, the economy is low, and the amount of waste is small.

[Brief description of the drawings]

FIG. 1 shows a correlation diagram between the water content and the regeneration rate of the ion exchange resins of Examples 1 to 3 and Comparative Example 1 at a regeneration level of 100 g / LR. In FIG. 1, SK104 is “Diaion SK1”.
04 ", SK1B is" Diaion SK1B ", SK1
Reference numeral 12 denotes "Diaion SK112".

FIG. 2 shows the conductivity of the eluate in Example 1 and Comparative Example 2.

FIG. 3 shows the total amount of organic carbonic acid in Example 1 and Comparative Example 2.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C08J 5/20 CET C08J 5/20 CET

Claims (11)

[Claims] 1. A monovinyl monomer having a content of 20 to 99.9 mol% and a crosslinkable monomer represented by the following general formula (1):
1 to 80 mol% (In the formula, n represents an integer of 1 to 5.) An ion exchange resin in which an ion exchange group is introduced into a crosslinked copolymer obtained by copolymerizing the same. 2. The water content of the ion exchange resin is 50%.
The ion-exchange resin according to claim 1, wherein the amount is not more than% by weight. 3. The ion exchange resin according to claim 1, wherein the crosslinking monomer represented by the general formula (1) is bis (vinylphenyl) ethane. 4. The ion exchange resin according to claim 1, wherein the monovinyl monomer is styrene. 5. The ion exchange resin according to claim 1, wherein the ion exchange group is a sulfonic acid group. 6. An ion exchange group represented by a quaternary ammonium base of the following formula -N ⁺ R ₁ R ₂ R ₃ X- (wherein R _{1 to} R ₃ are each independently an alkyl group having 1 to 4 carbon atoms or Wherein X represents an alkanol group and X represents an anion). 7. A copolymer of 20 to 99.9 mol% of a monovinyl monomer and 80 to 0.1 mol% of a cross-linking monomer in the presence of a polymerization initiator to introduce an ion-exchange group into the obtained cross-linked copolymer. In the method for producing an ion exchange resin, the following general formula (1) is used as a crosslinking monomer. (Wherein n represents an integer of 1 to 5). A method for producing an ion exchange resin, comprising using a bis (vinylphenyl) alkane represented by the following formula: 8. The method for producing an ion-exchange resin according to claim 7, wherein the crosslinking monomer is used in an amount of 5 to 50 mol% based on the total amount of the monomers. 9. The method according to claim 7, wherein the bis (vinylphenyl) alkane is bis (vinylphenyl) ethane. 10. A method for desalinating water using an ion exchange resin, wherein the ion exchange resin according to claim 1 is used as the ion exchange resin. 11. A method for producing ultrapure water using an ion exchange resin, wherein the ion exchange resin is used as the ion exchange resin.
A method for producing ultrapure water, comprising using the ion exchange resin described in the above item.